White Bark Pine

"Whitebark pine seeds are dispersed by Clark's nutcracker birds, which harvest seeds from cones, transport the seeds in a specialized throat pouch, and bury the seeds in caches throughout mountainous terrain. Because Clark's nutcrackers frequently cache seeds in open high-elevation areas, particularly burned areas...whitebark pine acts as a nurse tree (or tree island initiator) to facilitate the growth of other conifers and understory plants.

"About 98% of the range of whitebark pine in the United States is on public lands, including national parks, wilderness areas, and national forests....Given the protected status of most whitebark pine populations, and their distribution at high elevations, it is paradoxical that this species is severely threatened by two anthropogenic problems-introduced disease and fire suppression-which are complicated by recent upsurges in populations of mountain pine beetle (Dendroctonus ponderosae), perhaps due to lower overwintering mortality due to climate change.

"White pine blister rust, a fungal disease caused by the pathogen Cronartium ribicola, was inadvertently introduced to Vancouver, British Columbia, Canada in 1910 from Asia.... White pine blister rust spores germinate on the plant surface and grow into the pine through the stomatal openings in the needles. The infected branch holding the needles will often swell; after a year or more, the rust forms spores that are contained in blister - like sacks that erupt through the bark. When the blisters rupture they release bright orange colored aeciospores which infect the alternate host (most commonly gooseberry or currant plants). While hosted on these other plants, the rust produces basidiospores that are released in the fall, when gooseberry and currant drop their leaves, and infect more whitebark pine.

Whitepine blister rust expressed on a branch

"Between 1909 and 1940 and again from the 1970s to the 1980s, widespread mountain pine beetle outbreaks killed P. albicaulis throughout the U.S. Rocky Mountains, producing ghost forests. Mountain pine beetle infestations are again at high levels....The beetles kill trees by tunneling out galleries for their larvae to overwinter in the trunk, thereby girdling the water-transporting xylem.

Mountain pine bark beetle

"In some parts of the range of whitebark pine, particularly the northern Rocky Mountains of the United States and intermountain region, decades of fire suppression have also led to both progressive loss of whitebark pine and successional replacement by more shade-tolerant trees, such as spruce and fir, particularly at lower elevations...."What is JHMR doing to mitigate the whitebark pine die-off?Jackson Hole Mountain Resort has partnered with both the Bridger Teton National Forest and with the civil society organization TreeFight. In terms of blister rust infections, JHMR has mapped on the mountain all "plus trees" that phenotypically express genetic resistence to blister rust, collected seeds from those individuals to propogate in nurseries, and planted (as of 2012) 1000 of those saplings in the resort boundaries. In terms of beetle attacks, JHMR has applied a carbaryl pesticide to trees accessible from mountain roads, and has stapled verbenone hormone patches to more remote trees to aromatically deter beetles.

Verbenone hormone patch being stapled to a whitebark pine trunk

What is JHMR doing to raise awareness of the whitebark pine die-off?

In August, 2012, local artist Ben Roth created "Fallen", a 20 ft high by 60 ft long sculpture temporarily located adjacent to the pathway in Teton Village (see photo at top of page). The sculpture was constructed with multiple limbs that the JHMR trail crew cut from one deceased whitebark pine tree within resort boundaries. The large limbs were installed vertically in a cresting wave formation along the trail. Roth described the sculpture as a statement about the temporary nature of all living things.